中文摘要：

笔者以2004年～2011年A股市场663家高新技术企业为对象，实证研究了机构投资者的代表——证券投资基金持股对企业R＆D投入的影响，结果表明：将证券投资基金视为同质性机构投资者时，证券投资基金持股与企业R＆D投入正相关但不显著；而将证券投资基金视为异质性机构投资者时，并按照换手率特征将证券投资基金划分为长期投资者和短期机会主义者，发现长期投资者持股与企业R＆D投入显著正相关，而短期机会主义者持股与企业R＆D投入显著负相关。

英文摘要：

Based on 663 A-share market high-tech enterprises from 2004 -2011 ,this paper makes an empirical study of the relationship between the share holdings of securities investment fund which is a typical type of institutional investors and R＆D investment. The resuits show that securities investment funds do not have a significant positive correlation with R＆D investment when we regard securities investment funds as homogeneous institutional investors; we also find that long-term investors have a significant positive correlation with R＆D investment while short-term opportunists have a significant negative correlation with R＆D investment when we regard securities in- vestment funds as heterogeneous institutional investors and divide it into long-term investors and short-term opportunists.